The present invention relates to an inserter, designed to be used in hemodynamic studies and related operations.
As is known, in a surgical operation, the patient hematic flow is accessed by puncturing an artery vessel, typically a femoral or radial vessel, and the vessel being held in a pervious of patient condition by an inserter, which is a medical device to be used in surgical operations in general, for example during a hemodynamic monitoring, an electrocatheter implant, a diagnostic study procedure or any other desired surgical operating procedures, and is specifically designed to introduce, exchange and monitor other medical devices, for example catheters and electrodes, into a patient vessel.
An inserter, in particular, has generally a variable length, but a small size, for example from 15 to 90 cm for a femoral and radial artery, and is specifically selected based on its inner diameter, corresponding to the size of the device to be introduced thereinto.
The inserter, which is held at its target position through the overall duration of the surgical procedure, and also for several days after such a procedure, conventionally comprises a rigid low friction material extruded tube, usually made of FEP and PTFE, having a small thickness and a tapering end portion.
Some inserters, moreover, are structurally reinforced through their thickness by a metal armoring construction to prevent the inserter tube from bulging.
The proximal portion of the inserter is usually coupled to a hemostatic valve, or rigid plastic component including a silicone material diaphragm, designed for insulating the inserter from the encompassing outside environment, which valve, designed to prevent blood from exiting and air from entering the patient vessel, comprises a pre-cut silicone diaphragm for axially holding an auxiliary device which is thus “encompassed” by the silicone material to provide a tight sealing.
On a side of said valve and downstream thereof is furthermore provided a line contacting the patient blood for continuously monitoring its patient pressure.
The above inserter is generally installed or implanted by using the so-called Seldinger's technique.
According to this procedure, a patient vessel is punctured by a needle, and then into this needle a guide wire having a suitable length and adapted to be arranged at a target point of the vessel is introduced.
Then, the needle is withdrawn and on the guide the inserter-dilatator system is caused to slide.
The dilatator is a flexible tube, made of a low friction material, such as PTFE, comprising an elongated tip to facilitate the inserting operation, and has an outer diameter equal to the inner diameter of the inserter.
Then, a suitably designed proximal system allows the dilatator to be engaged in and disengaged from the inserter, after having withdrawn the latter, thereby, at the end of such an operation, only the inserter will be held in the patient vessel.
Accordingly, the inserter must have such a stiffness as to prevent the vessel from closing because of its resilient properties.
In this connection it should be pointed out that the above mentioned Seldinger's procedure allows the vessel to be opened by a dilating hole and not, as one could think, by a cut.
In other words, the above procedure exploits the deforming resilient capability of the vessel, and is also very useful for reclosing the vessel at the end of the operation, since an incision or cut would be much more difficult to heal than a hole; the vessel being closed by manually pressing it or by using specifically designed closure systems, such as percutaneous sutures or collagen based systems.
In the above mentioned operations, it is sometimes moreover necessary to change the inserter and replace it by a larger or smaller diameter one, for example in an implant procedure for implanting ventricular assistance systems, to allow an application of a larger diameter device.
At present, the above operations require the installed inserter to be removed, and repeat the Seldinger's procedure, to relocate said inserter.